Naphtha can be a low value petrochemical stream found in petroleum distillate streams from oil refinery processes. Naphtha that is derived from the distillate of the crude still, i.e., straight run naphtha, can contain a variety of components, depending on the composition of the crude source. Straight run naphtha typically includes large amounts of straight and branched paraffins, and can further include olefins and/or aromatics.
As demand for petrochemical products grows, there is increased interest in converting low value naphtha streams into high value petrochemical products, including ethylene and propylene. Several technologies for producing light olefins, such as ethylene and propylene, are known in the art, for instance by fluid catalytic cracking (FCC), deep catalytic cracking (DCC), advanced catalytic olefins (ACO) processes, steam cracking, propane dehydrogenation, and olefin metathesis.
For example, European Patent No. 1117750 discloses a catalytic naphtha cracking process for producing olefins using a zeolite catalyst including phosphorus and a promoter metal. U.S. Patent Publication No. 2007/0082809 discloses hydrothermally stable porous molecular sieve catalysts, which can be used in catalytic cracking reactions, including producing light olefins from naphtha. U.S. Patent Publication No. 2007/0010699 discloses a process for producing light olefins from hydrocarbon feedstock using porous molecular sieve catalysts having a water-insoluble metal salt and a phosphate compound. International Patent Publication No. WO 2011/162717 discloses a method of producing alkenes by the dehydration of alcohols using a metal-modified zeolite. U.S. Patent Publication No. 2007/0209969 discloses a catalyst for use in cracking heavy feedstocks to produce lower olefins that can include an alkaline treated zeolite having a silica to alumina ratio of less than 45.
However, there remains a need for methods of producing high yields of ethylene and propylene from naphtha.